i apologize, ive been posting a lot of questions lately, but im almost there as far as getting the car dialed in. the only thing left is getting it to run a little leaner (i think) right now im getting 12.5 mpg (assuming a 12 gal tank? for an 84) theres that and the fact that when i stomp on it (above 3/4 throttle) the car will stumble. i do have slightly bigger jets than before on the carb also, and a dual air snorkel..i have access to the 2 a/f mixture screws at the base of the carb, is this my best way to lean it out a little? i was thinking maybe give them a half a turn im guessing clockwise to start out with. i dont have a way to check what the actual a/f ratio is, is there a way that i can check that on my non computer controlled carb? thanks for any input. im trying to get the mpg better as i have an 8 hr move comin up.

i also thought that getting a k/n air filter might help get a bit more air..but i hear they dont exactly do much more..idk

 

Well, the screws are really only going to impact idle. The only way to check the AF ratio is with a gauge. However, there are some things you can do:

1) What is the timing setup? This will have the biggest impact on MPG's. Especially if you aren't running vacuum advance.
2) Why would you up the jets? Most Holley carbs are too rich to begin with (when put on a nearly stock motor).

 

its a qjet that was converted to non ccc and got a vac advance dist. with 8mm plug wires. originally i had some LT headers and a 3" true dual set up that i was gonna put on before i found out i was moving to an emissions state. i figured with that and the dual snorkel there would be enough airflow to warrant the slightly bigger jets. but the carb was already done when i found out about the move. the car runs really well except past 3/4 throttle or if i punch it too quickly. the timing is set for 12 initial , 34-36 total because i was told it likes the 10-12 initial range with vac advance dist. so those arent a/f ratio screws they are idle mixture screws? i get those terms mixed up since i am still learning. maybe try turning it down to 10 maybe? i need to double check the timing anyway since we did it with the old style light and it was hard to see the marks (location is terrible!)

but i was hoping there was some way to lean it out some other than timing since the car is running so well besides the few issues. ill give it a look on the interwebs and this site, but im wondering how the gauge set up for a/f ratio works like where it hooks too etc. but i dont think ill have the money for that before i make the excursion